David writes:
<<When setting the gram resistance of on underlevers, what is the best
point at which to take the measurement. The higher you lift the lever,
of course, the greater the resistance, so where in the travel should the
reading be taken? >>
Greetings,
I got them gauges, and I been to the convention classes, and I have seen
better technicians than I measure each one. However, I have installed a
goodly number of these kits and I don't measure the springs that way, anymore. The
dampers damp, and you can't feel them in the key without trying.
I turn the tray upside down, and bounce it up and down. The bass
dampers on a D will usually work with sufficient underlever spring strength so
that the underlever is supported by the spring when you turn the rack upside
down. If you give a slight up and down bounce to the tray, the weight of the
underlever is enough so that it will just barely move downward against the spring
tension. I have measured this eyeballing procedure at about 15 grams in the
bottom end.
At the treble terminus of the spring parade, I like the spring to be able
to just barely stay in contact with the underlever, and upside down, the
underlever will slightly hang off the felt.
Between these two indicators, it is easy to bounce the tray with one end
on the bench, and tighten or loosen the springs until the assembly moves like
the Radio City Rockettes. There may be a sway in the progression,(like the
very bottom of the bass clearly less ready to dance, needing a stronger bounce
to come off the felt), but that will be of little importance if there is
evenness and no extremes.
This procedure presumes that there is good pinning, traveling, alignement
and spacing on the dampers and the wires. The low spring pressure will not
cover up other problems, but it leaves a very transparent damper feel.
Regards,
Ed Foote RPT
http://www.uk-piano.org/edfoote/index.html
www.uk-piano.org/edfoote/well_tempered_piano.html
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